1. Field of the Invention
The invention relates in general to an image scanner module and the scanning method thereof, and more particular, to a double-side image scanner module which uses a single image extraction and light source compensation to perform double-side scanning of a document, and a scanning method of the same.
2. Description of Related Art
Due to the technical advancement and rapid development, electronic industry has become one of the most important industries in modern society. Many high-performance calculating systems are produced, and more and more electronic products have actually frequently applied to daily lives. In recent years, the greatly improved processing speed and data storage of processor and computer related products greatly enhance the performance for graphic process, such that image-processing equipment such as optical scanners or digital camera commonly used.
Generally speaking, most of the conventional scanners are used for single-side image scanning. To scan double-side image of a document, manual page turning or two image extraction apparatus are required. Referring to FIG. 1, a conventional double-side image scanner module that uses two image extraction apparatus to read both sides of a document is shown. As shown in FIG. 1, the double-side image scanner module 100 comprises a U-shape rotating apparatus 102, a first transparent window 104, a first image extraction apparatus 106, a second transparent window 108, and a second image extraction apparatus 110.
Further referring to FIG. 1, while using the double-side image scanner module 100 for scanning, a document (not shown) is fed along the feeding direction and guided into a U-shape rotating apparatus 102 by a roller 114. During the paper feeding process, the document will pass through the first transparent window 104, under which the first image extraction apparatus 106 is installed to read the first-side image of the document. Another roller 116 is further installed in the U-shape rotating apparatus 102 to guide the document proceeding further.
The second image extraction apparatus 110 is installed under the second transparent window 108. When the document travels through the second window 108, the second-side image of the document is read by the second image extraction apparatus 110. The document is then guided by the roller 118 towards the paper discharging direction 120.
In the above double-side image scanner module 100, two image extraction apparatus 106, 110 are required, such that the overall structure is more complex. Further, the first image extraction apparatus 106 is located above the second image extraction apparatus 110 and the second transparent window 108, so that the height reduction is difficult to achieve. Therefore, this type of double-side image scanner module normally has a large volume.